The dread Mysteries, full of such great salvation, which are celebrated at every Liturgy, are also called a Thanksgiving [Eucharistia] because they are the remembrance of many benefits, and they signify the culmination of God's Providence towards us, and in every way cause us to be thankful to Him.
They are the Church who are a people united to the Priest, and the flock which adheres to its Pastor. From this you ought to know that the Bishop is in the Church, and the Church is in the Bishop; and if anyone is not with the Bishop, that he is not in the Church, and that those who flatter themselves and creep in, and commune secretly with some, do so in vain, not having peace with God's Priests; while the Church, which is universal and one, is not cut nor divided, but is indeed connected and bound together by the bond of Priests who unite with one another.
As therefore the Lord does nothing without the Father, for says He, 'I can of mine own self do nothing,' so do you, neither presbyter, nor deacon, nor layman, do anything without the bishop.
